Discussion on the Coordinate Maintenance of BDS Monitoring Station   

    The monitoring stations of BeiDou 2nd generation navigation satellite system are built based on the 1st generation system, for the convenience of management, monitoring antennas are installed on the roof of the monitoring station. So their stability are not enough. At the same time, the coordinate system of BeiDou 2nd generation navigation satellite system is 2000 China Geodetic Coordinate System (CGCS2000) at present and the calculation error is out of range. According to these problems, the effect of timevarying and ground subsidence are analyzed in this paper, and the error order of magnitude processed by methods of time varying effect is also pointed out at present. We discuss the initial implementation and refinement realizations of the World Geodetic System 1984(WGS84) frame, which used as the terrestrial reference system for GPS. Finally, for the situation of BDS monitoring stations, we propose to set up coordinate time series through Global Navigation Satellite System (GNSS) continuous observation to maintenance the coordinate of monitoring station. Some suggestions are put forward for the monitoring station construction, data processing etc